They look lovely. I was looking at these on ebay the other day and they have been adapted for rats already with shelves in etc... Only cost between Â£100-Â£200 on there.
I did contemplate getting one but I thought they were far to big for my house, though looking at yours compared to the surroundings I dont think there as big as I thought lol.
How many rats do you have in each one?
I love what you have put in them, those baskets (blue one in 2nd pic) How do you attatch them onto cage.
Also I havent seen one cage yet with a wheel on? Every Rat ive had has loved the wheel and you can buy big ones for rats.